plural noun

in some classifications
: a division of Eulamellibranchia comprising extinct chiefly Cretaceous bivalve mollusks with one valve elongate, conical, and thick-shelled and the other small and fitting like a lid on the first
adjective or noun
adjective or noun

Word History


New Latin, from Latin rudis rude, raw + -ista -ist

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Dictionary Entries Near Rudista

Cite this Entry

“Rudista.” Dictionary, Merriam-Webster, Accessed 30 Sep. 2023.

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